Valve for player-pianos.



G. V. JAMESON.

VALVE FOR PLAYER PIANOS.

APPLIGATION FILED SEPT.. z, 1911.

1,081,533, Patented Deo. 16, 1913.

CirAInns' v. JAMESON, or arranca-ILLINOIS..

VALVE non PLAYEPIANS.

Speincatin of Letters raient.

Patented Dee. 16,1913.

To" all;v whom it 'may' concern f Beit known that'I, iCi'erAizLns .VJ J AMsoN, a citizenr ofthe-UnitedStates' of America, and a resident of Chicago, county of Cook, and AState of Illinois, have invented certain new and useful Improvements in'Valves for Player-Pianos,I of which the following is a specification.

My invention relates to valves for player pianos and has for its object improvements in such valves and theirassociat'edparts.

In the accompanying drawings-Figure l is asection on theibroken line 1--1 of Fig. 2, and shows the valve and associated parts; Fig 2 is a plan, partly broken away, of a portion of the vacuum chest and connected parts; Fig. 3 is a section on line 3-8 of Fig. 2; and Fig. 4 is a detail.

In the said drawings A represents the interior space of a vacuum chest,the bottom and sides of which are of wood, while the top is composed of a metal plate B having ports C therein. A tube D connects the space A with a suitable pump for maintaining the desired degree of vacuum.

In the bottom A1 of the vacuum chest is a recess E having its top closed by a diaphragm or pouch E1. Connected with the recess E is an air channel F which communicates, by means of a rubber tube Gr, with a port in the tracker bar of the player. A branch F1 (Fig. 3) of the channel F connects said channel with the vacuum chest A. This branch is closed by a plate F2 which has a minute hole in its center so that the actual communication between the chest A and the recess E is that afforded by this small hole in plate F2. The plate B has a valve sea-t around each port C, and valves H on stems H1, close these ports. These valves have rubber or leather faces as shown. On the lower ends of the stem H1 are adjustable heads H2 which rest on the diaphragm E1. Secured to the metal plate B is a metal cap K having a port K1 adapted to be closed by the upper face of the valve H when that valve is in its upper position. When the valve is in its lower position it closes the port C. The metal around the port K1 is bent inward as shown to form a seat for the valve H. Over the port K1 is a bridge K2 having a central pin K3 which enters a hole in the stem H1 for the purpose of guiding the valve H. This hole has a felt or other soft bushing H3 as shown in Fig. 4. This is for the purpose ofavoiding metall-ic contact in' moving parts. l

Secured to the"vacuum chest A1, and in association" with 'each valve H,"is a pneumatic P which is connected to' some one of the striking actions ofI the piano. This pneumatic is' connectedV with the interior of the cap Krbya passageway P1.

Thetracker bar is a bar or plate having perforations orports therein, each one of theports'bing connected 'by a rubber tube G with the space under a corresponding diaphragm E1, and also, through the branch channel F1 and hole F2 with the interior of the vacuum chest A. A perforated sheet of paper representing music is caused to move over the ports of the tracker bar at a desired speed. As long as the paper covers a particular port in the tracker bar, the air in the pneumatic tube G, and in the space E under the diaphragm E1 will be withdrawn through the opening F2 so that the same degree of vacuum will exist in these spaces as that which exists in the chest A. In this condition the valve H closes the port C, and outside air enters the port K1 and flows through the passageway P1 to the pneumatic P.

Vhen a perforation in the paper coincides with a port in the tracker bar, air will flow through the connected tube G to the corresponding recess E, and the dilference in air pressure on the two sides of the diaphragm E1 will cause that diaphragm to rise. This movement of the diaphragm moves the valve H so as to open the port C and close the port K1. In this condition the inside of the pneumatic P is in direct communication with the vacuum chest A with the result that the pneumatic collapses and causes an operation of a corresponding piano action. Vhen the moving paper again closes the port in the tracker bar, the air in the tube G and the recess E will be withdrawn through the small opening F. This leaves greater air pressure on the top of the valve H than eX- ists under the diaphragm E1 with the result 'that the valve is shifted so as to open the port K1 and close t-he port C. In this condition outside air flows through the port K1, the interior of the cap K and the passageway P1 to the pneumatic P. This permits the parts to return to original position as shown in the drawings.

It has heretofore been the practice to make the vacuum chest, valves and connected parts, entirely of wood or entirel of metal. Vood is preferable in that it is c eaper and easier to handle. Wood is disadvantageous by reason of being partially pervious to air and being subject to atmospheric variations which cause warping, splitting, swelling, contracting, etc. This is particularly obj ectionable in valve seats and in the thinner parts of the chest. Metal is preferable in that it can be made air tight and the valve seats can be kept in proper condition. Metal is objectionable because it is more eX- pensive than wood and also because it is not desirable to have inetal in a piano in a forni in which it can possibly act as a sounding board.

It will be observed in the preceding description that I have combined wood and metal in such a form as to obtain the advantages of both and the objections of neither. The main and heavy parts of the chest are made of wood while the valve seats are in a metal plate which binds the wooden parts together and tends to prevent theni from warping and splitting. The removable caps K are made in a form which permits an easy and rapid flow of air to and from the pneuniatics, and being individual for each valve they provide easy access thereto.

Vhat I claim is A valve, upper and lower seats therefor, an elongated aXial opening in the stein of the valve, a felt or other soft bushing in said opening, and a fixed pin adapted to enter said bushing and lit therein so as to guide said valve.

Signed at Chicago, Ill. this 29th day of August 1911.

CHARLES V. JAMESON.

Copies of this patent may be obtained for ve cents each, by addressing the Commissioner of Patents, Washington` D. 

